Electronic documents can be shared by an author with a recipient, or a plurality of recipients (referred to herein as “users”) using commonly available services and applications, In a simple implementation, electronic mail applications often permit the attachment of documents to electronic mail for communication to an intended recipient. Alternately, cloud applications, such as Dropbox™, allow an author to send a link to a recipient which, when invoked, provides access to a document, which may be stored on a database accessible over a network.
In some cases, document authors share documents that may be extrinsically related to other documents. Examples of extrinsic relations include (a) subsequent versions of a document, (b) documents having shared document content, (c) documents having a shared document identification number, and (d) documents having a shared parent document.
Various systems and methods have been proposed for tracking extrinsically related documents. Such systems may, for example, attempt to prevent a recipient from accessing an outdated version of a shared document. U.S. Pat. No. 7,836,019 describes, in an embodiment, when a user opens one of the documents that was downloaded from the document management storage, a check is performed to determine whether the document opened is the most recent version. This check may be performed in an embodiment by comparing unique identifiers of the two copies of the document (e.g., the copy residing on the user's desktop and the copy stored by the document management system). In an embodiment, if the user's copy of the document is not the most recent version, a message may be sent to the user asking if the user wants to have the user's copy updated.